Any heating engineers here? Colder room in new build?

After a bit of info as I’m struggling with this.

we live in a new build property (4 years old), we are 50 yards from the sea so weather this time of year can be extreme to say the least.

Its a relatively large house with a wet underfloor heating system downstairs and rads upstairs.

The house is always warm, but my daughters room which is large and directly above the garage gets cold at night obviously because there is no heat below helping to raise the temp of the room.

I’ve bought a Nest system for the upstairs zone hoping it would help but nothing (didn’t think it would but it looks good ;-)). I cannot have the heating on constantly because the rest of the upstairs get unbearably hot.

The thermostat is located on the upstairs landing and due to efficient heat from the underfloor heating downstairs which obviously rises the heating clicks off quite quickly and does not give sufficient time for her large bedroom to heat up.

I feel the radiator is undersized for the room and what with the lack of heat below the room.

Is it worth me paying to have a larger rad installed? I can’t see it helping much as the temperature will still drop when there is no heat source on?

Could anyone recommend a good quality “background” heat that may work during the night in Winter months?

I don’t need to reinvent the wheel here just looking for a good solution to the problem.

Cheers

I also have a house with wet underfloor heating and rads upstairs. I’m not a professional but how about a radio controlled portable thermostat you can put in your daughters room, then individual thermostatic valves on all the radiators in the house? That should keep her room heated when the rest of the house is already warm, and the valves can all do their job individually. Probably work out cheaper than running a secondary heater in her room I would have thought too?


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A person who sorts out your heating system is not an ‘Engineer’

Sorry, couldn’t help it. Just doing my best not to allow further devaluation of the engineering profession.

What is the bedroom floor made of and is there any insulation under it.

What are the room and radiator dimensions?

When the room is cold is the radiator on and work and just not putting out enough heat or is the heating off because the area where the 'stat is is warm enough?

How close is the room the heating control valves, the RR solution is to have a separately controlled circuit for that room.

I would first check the level of in-floor insulation for her room. The garage below should (for purposes of insulation) be regarded as external space and so her floor should be crammed full of insulation to stop her room losing all its heat. If the insulation is good enough, her room should not cool down more quickly. It should also wanm relatively quickly as a rad will heat the room faster than an underfloor system.

BTW, does your heating system run on 2 water temperatures, usually wet underfloor systems run on a lower temperature water than rads. Rads need at least 60 Deg C or more to work effectively, and wet underfloor doesn't need nearly that much temp. So it is possibly that your rads are not working every effectively if the setpoint is too low.

Dave

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Originally Posted by RobDad

I also have a house with wet underfloor heating and rads upstairs. I’m not a professional but how about a radio controlled portable thermostat you can put in your daughters room, then individual thermostatic valves on all the radiators in the house? That should keep her room heated when the rest of the house is already warm, and the valves can all do their job individually. Probably work out cheaper than running a secondary heater in her room I would have thought too?


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I'd be going down this route.

Have you considered a 2nd radiator in the room ? I have a fairly large lounge and it only had one small radiator (under the window) so was always cold - I added 2 vertical radiators to the walls.

The pipes can all be run off the same radiator but of course the thermostat still needs to fire the boiler.

It did make my room much warmer. The only other alternative could be smart radiator valves but expensive to implement on a large house.

As others have said, make sure floor is well insulated or even consider heating the garage (esp. if used as workspace rather than to store a car).

Apart from that, get an electric heater with thermostat to provide background heat in winter. In my experience simple radiator valves don’t work well.

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Originally Posted by noTAGlove

A person who sorts out your heating system is not an ‘Engineer’

Sorry, couldn’t help it. Just doing my best not to allow further devaluation of the engineering profession.

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They can be, as there is more than one type of engineer.

https://www.ciphe.org.uk/

I would get zoned heating.

I have the Honeywell Evo for similair situation to yours. Except my duaghters room is in the loft so is much , much warmer than the middle floors. I prefer a cool bedroom whereas the kids have a slighlty warmer room/

Also I can conttol the rooms as I use them . eg Playroom only warm during the day, Study and TV room in the evening. Lounge all day etc,

It's really room by room control and can be incorporated to include under floor heating and radiators.

It's easy to retrofit, The room TRVs screw on top of exisiting ones.
These blokes are really helpful

https://theevohomeshop.co.uk/

Also as others have said check insualtion below.

Thanks for the replies this far gents.

The floor is timber with plenty of insulation (I’ve checked), the room when the heating is on is warm but as she has her door closed all the time this makes matters worse as the upstairs landing heats up quicker.

Spoke to a heating guy about the smart TRV’s, his opinion was they are ok but expensive and not sure if the cost could be recouped and also questioned how Ming they would last.

A bigger rad or additional rad would help matters but would not stop the temp drop in the evening. The garage isn’t cold but is a garage so no heat and her bedroom has a large window and 2 external walls.

I feel a secondary source of background heat is the way to go, but what? Oil filled rad seems a good option but would want a nice looking one, not noisy and programmable for time and temp?

A stupid problem I know but she’s 9 and it can get chilly in there, when I was a kid I would have been told to sleep in a jomper!

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Originally Posted by eagletower

I would get zoned heating.

I have the Honeywell Evo for similair situation to yours. Except my duaghters room is in the loft so is much , much warmer than the middle floors. I prefer a cool bedroom whereas the kids have a slighlty warmer room/

Also I can conttol the rooms as I use them . eg Playroom only warm during the day, Study and TV room in the evening. Lounge all day etc,

It's really room by room control and can be incorporated to include under floor heating and radiators.

It's easy to retrofit, The room TRVs screw on top of exisiting ones.
These blokes are really helpful

https://theevohomeshop.co.uk/

Also as others have said check insualtion below.

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I have looked at the Evohome, looks a good system, but to do it properly I would need to spend nearly £1000 for the kit and all TRV’s for the upstairs and the issue is literally one room so is a waste of money.

shame it can’t be done for just one rad.

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Originally Posted by gilford

A stupid problem I know but she’s 9 and it can get chilly in there, when I was a kid I would have been told to sleep in a jomper!

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Remember when we were kids had ice inside bedroom windows.

In my old house one of the bedrooms had the same issue.

I bought a gel heater - costs a lot more than an oil one but the heat was consistent and comfortable. Also wall hung and looked much nicer.

My one had a timer to come on at night and maintain the temp then turn off.

https://www.heatershop.co.uk/haverla...tric-radiators

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Originally Posted by gilford

I have looked at the Evohome, looks a good system, but to do it properly I would need to spend nearly £1000 for the kit and all TRV’s for the upstairs and the issue is literally one room so is a waste of money.

shame it can’t be done for just one rad.

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In your case it does sound like overkill. My house is solid brick but then has mutliple extenstions so all the rooms heat up and lose heats at differnet rates so was well worth the investement just from a comfort point of view.

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Originally Posted by gilford

After a bit of info as I’m struggling with this.

we live in a new build property (4 years old), we are 50 yards from the sea so weather this time of year can be extreme to say the least.

Its a relatively large house with a wet underfloor heating system downstairs and rads upstairs.

The house is always warm, but my daughters room which is large and directly above the garage gets cold at night obviously because there is no heat below helping to raise the temp of the room.

I’ve bought a Nest system for the upstairs zone hoping it would help but nothing (didn’t think it would but it looks good ;-)). I cannot have the heating on constantly because the rest of the upstairs get unbearably hot.

The thermostat is located on the upstairs landing and due to efficient heat from the underfloor heating downstairs which obviously rises the heating clicks off quite quickly and does not give sufficient time for her large bedroom to heat up.

I feel the radiator is undersized for the room and what with the lack of heat below the room





Is it worth me paying to have a larger rad installed? I can’t see it helping much as the temperature will still drop when there is no heat source on?

Could anyone recommend a good quality “background” heat that may work during the night in Winter months?

I don’t need to reinvent the wheel here just looking for a good solution to the problem.

Cheers

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move the stat, add more insulation to garage ceiling and start improving air tightness to garage A larger rad will becomes pointless as soon as stat clicks off.

Try bleeding the rad, opening the lockshield a bit more but this is only any good while stat is active

My son's room is on the back of the house with period sash windows and stone frames. This makes the temperature in the room plummet when there is an easterly wind as it just comes straight through. I bought a Dyson Hot & Cold before Christmas and have it set to 20 degrees as a back up. Its quiet, looks pretty cool and works a treat, much better than the oil filled rads IMO.

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Originally Posted by noTAGlove

A person who sorts out your heating system is not an ‘Engineer’

Sorry, couldn’t help it. Just doing my best not to allow further devaluation of the engineering profession.

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There’s always one.



OP, i’m A heating ‘engineer’ by profession and I have a granny flat that is above the double garage, from experience I would go down the portable heater as suggested.

On the upside, the room is pleasantly cool during a hot summer.

Well we do design and development just finishing off a contemporary house ..we have used underfloor wet systems for many years , we tend not to mix rads and underfloor . The main problem you have is that it appears your system is not zoned so each room can be controlled by a roomstate either wireless or wired , seems very mean and poor practise not to have zoning !.
The only sensible solution without spending a fortune would as has already been mentioned to fit thermostatic rad valves it maybe if you speak to a good plumber he could incorporate a motorised valve into the system as well so only your daughters room gets heated ...my advice would be seek out a good experienced plumber ! I personally have not heard of a system which is not zoned back to the manifold and on top of that not to have thermostatic rad valves fitted seems very odd ....


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I do have zones, all of the downstairs underfloor is zoned for each room and all work independently, upstairs is its own zone and each rad has a TRV.

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Originally Posted by gilford

The floor is timber with plenty of insulation (I’ve checked),

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If it only has rockwool/earthwool in it, consider overplating the garage ceiling with phenolic insulation (Kingspan, Celotex or Quinntherm) to at least 100mm minimum assuming you'll still have a fair height to the garage.
The difference between this and rock wool type insulation for heat retention is huge.

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Originally Posted by noTAGlove

A person who sorts out your heating system is not an ‘Engineer’

Sorry, couldn’t help it. Just doing my best not to allow further devaluation of the engineering profession.

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My dogs an engineer, give him a kick up the arse and he'll make a bolt for the door.




I haven't got a dog really

I'm an Architectural Technologist if it helps i may be able to advise on the fabric but maybe not the CH Design as these are generally designed by specialists (who are engineers). We often spec these situations and rarely have any issues and we work with many of the nationals (i.e. Talyor Wimpey, David Wilson etc.) and the NHBC who are a royal PITA. Heat loss through that floor should be relatively low as cold air falls and warm air rises, and also the garage is considered a semi-external space from the perspective of thermal efficiency and heat loss design and the 'U' Value through that floor should be better than the ground floor to be honest.

The insulation shouldn't be just mineral wool packed in there though but foil-backed PIR board held on retaining clips / battens and a breather membrane to hit modern Part L1A requirements. Either that or you could retro-fit / under-board the garage ceiling with an insulated plasterboard but that may mean messing with lighting (and losing a bit of headroom) and the powered door if you have one (depending on how it's wired). We often under-board them anyway nowadays as it's pretty cheap to do and it boosts the SAP's that we offset elsewhere (and reduces cold bridging through the joists).

The other thing to consider is the roof as most of the heat loss will be via that (the garage below doesn't help though). Just a thought especially if it's a room in the roof.

Other than that then it may be an under-sized or poorly positioned rad and as the OP said maybe consider relocating the stat or adding a separate zone but it's probably best to ask a heating engineer for advice on that.

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Had a similar problem with a room, and had lots of complex solutions offered to solve it.

In the end we simply put an electric programmable radiator in there. Problem solved. Simple. Can set the desired temperature and times you want it on, all in the inbuilt programmer.

Does it cost anything to use? Yes it uses electricity. But pretty cost effective in my opinion and it has the main advantage which is it works?

We used one of these. Easily installed by any electrician.

https://www.dimplex.co.uk/product/q-...ctric-radiator

Online calculator for radiator output needed for a room.

https://www.dimplex.co.uk/room-heating-calculator

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Originally Posted by oldoakknives

Had a similar problem with a room, and had lots of complex solutions offered to solve it.

In the end we simply put an electric programmable radiator in there. Problem solved. Simple. Can set the desired temperature and times you want it on, all in the inbuilt programmer.

Does it cost anything to use? Yes it uses electricity. But pretty cost effective in my opinion and it has the main advantage which is it works?

We used one of these. Easily installed by any electrician.

https://www.dimplex.co.uk/product/q-...ctric-radiator

Online calculator for radiator output needed for a room.

https://www.dimplex.co.uk/room-heating-calculator

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Probably the most economical solution to be fair.

I guess working in the industry we tend to overthink things as we've had heating / CO2 emissions / building fabric efficiency rammed down our throats for the last 20 years and have become institutionalised (similar to the motor industry i suspect). The cost to stick a panel heater in there would be far more economical than retro-upgrading the fabric (wherever it's failing). Saying that to replace / upgrade the insulation in the separating floor wouldn't be difficult or costly to do and wouldn't hurt (if it's just crappy mineral wool in there like many developers use to save some money), and if you were going to do that you'd do it from underneath to save pulling the flooring up. Guess it depends on how long you plan on staying there and whether you can be arsed.

I understand the principles of heat transfer etc but I’ve no experience with domestic heating systems. However, it’s clear to me that many central heating systems are quite crudely designed, I live in a modern detached house and mine could be better. We had a similar problem, the bedroom on the corner was over the garage, had two outside walls, two windows, and faced the prevailing westerly winds.

The two easiest ‘quick fixes’ are to leave the door open to allow warmer air to enter, and to fit thicker carpet and underlay. I’d also consider an oil-filled radiator plugged into a timer.

I grew up in the 60s in a cold house with no central heating, but in those days we only used bedrooms for sleeping! thesedays kids bedrooms are like dens, they spend a lot of time there, so the room does need to be warm.

The final solution to our cold bedroom issues was the stepdaughter reaching adulthood and leaving home.....but you’re a long way from that!

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Originally Posted by walkerwek1958

I understand the principles of heat transfer etc but I’ve no experience with domestic heating systems. However, it’s clear to me that many central heating systems are quite crudely designed, I live in a modern detached house and mine could be better. We had a similar problem, the bedroom on the corner was over the garage, had two outside walls, two windows, and faced the prevailing westerly winds.

The two easiest ‘quick fixes’ are to leave the door open to allow warmer air to enter, and to fit thicker carpet and underlay. I’d also consider an oil-filled radiator plugged into a timer.

I grew up in the 60s in a cold house with no central heating, but in those days we only used bedrooms for sleeping! thesedays kids bedrooms are like dens, they spend a lot of time there, so the room does need to be warm.

The final solution to our cold bedroom issues was the stepdaughter reaching adulthood and leaving home.....but you’re a long way from that!

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My dad always used to say to us 'put a bloody jumper on!'.

Central heating design and energy efficiency / thermal design used to be the remit of Architects but not anymore as they've become separate disciplines altogether (so bloody complicated and we don't have the time anymore). From my experience, particularly with large modern houses and all the reams of legislation we need to pick through before it can hit the market it's so easy to get it wrong especially with combination space heating principles (i.e. underfloor, wet rads, air con) and systems (fossil fuel, pv, ground source heat pumps, air source heat pumps, biomass etc etc) and it sometimes happens unfortunately. Problem as well is we may spec something and the developer puts something else in to save on costs (which can add up to many millions with Barratts for example building over 17,000 units last year alone).

The other things that can cause problems are amount of glass, orientation / solar gain, exposure / prevailing wind, proximity to trees believe it or not and a few others but these should be considered at the design stage and allowed for.

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Originally Posted by walkerwek1958

I understand the principles of heat transfer etc but I’ve no experience with domestic heating systems. However, it’s clear to me that many central heating systems are quite crudely designed, I live in a modern detached house and mine could be better. We had a similar problem, the bedroom on the corner was over the garage, had two outside walls, two windows, and faced the prevailing westerly winds.

The two easiest ‘quick fixes’ are to leave the door open to allow warmer air to enter, and to fit thicker carpet and underlay. I’d also consider an oil-filled radiator plugged into a timer.

I grew up in the 60s in a cold house with no central heating, but in those days we only used bedrooms for sleeping! thesedays kids bedrooms are like dens, they spend a lot of time there, so the room does need to be warm.

The final solution to our cold bedroom issues was the stepdaughter reaching adulthood and leaving home.....but you’re a long way from that!

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Sounds like you have been in my exact situation.

I like some of the dimplex rads as linked above but I don’t need a fixed solution as it’s only for the cold nights, what oil filled rad would you all recommend?

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Originally Posted by gilford

Sounds like you have been in my exact situation.

I like some of the dimplex rads as linked above but I don’t need a fixed solution as it’s only for the cold nights, what oil filled rad would you all recommend?

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Following with interest.

Would be good to know the pros/cons for gel based vs oil base vs electric panel.

Coincidentally, an advert for this just came on TV: https://www.fischerfutureheat.com/el...store-heaters/ - first time I've heard of them...

Better looking ones here - but interested to know how effective they really are:

https://www.amazon.co.uk/s/ref=lp_31...2&rnid=3147661

Late into this one.....

Do you have TRV's on the upstairs radiators? If so just close the other rooms down and leave your daughters open wide. Worth checking the locksheild valves are all open fully before you start all of this.

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Originally Posted by gilford

Sounds like you have been in my exact situation.

I like some of the dimplex rads as linked above but I don’t need a fixed solution as it’s only for the cold nights, what oil filled rad would you all recommend?

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We had one but we gave it away years ago. Any form of electrical heating will be potentially costly, avoid fan heaters because the motor also consumes power butthey’re very good for warming a room fairly quickly.

Have to smile at the emphasis thesedays on controlling heating from your phone etc. Getting the hardware of the heating system right is the way to gain improvement, the ability to heat rooms separately to a given temperature would be ideal, that needs valves and pipework........if I’m wrong on this one I’m happy to be corrected.

The one room in my house that MUST be warm is my study/watch work room, can’t work with cold hands and wearing pullovers ir anything with long sleeves is a no-no. I suffer mildly fron Reynauds Disease and I have to keep my hands warm, fingertips get numb if I don’t. Ironically, my room’s south facing and it gets too hot to work in the summer!

As for the big housing developers cutting corners and costs......don’t get me started. Much of what goes up nowadays is dismal, too small, crammed together, tiny garages that are useless, insufficient parking space, cramped cul de sacs, small rooms......but to their credit they’re usually warm unlike the house I grew up in.

Electricity for heating is very costly but convenient.

Electricity cost is around 13p/kWh whereas gas is 2.8p kWh. Say you boiler is 70% efficient, making is 4p kW/h (2.8/0.7) equivalent.

So heating with electricity is 3.25 times the price of gas. Ouch!

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Originally Posted by walkerwek1958

As for the big housing developers cutting corners and costs......don’t get me started. Much of what goes up nowadays is dismal, too small, crammed together, tiny garages that are useless, insufficient parking space, cramped cul de sacs, small rooms......but to their credit they’re usually warm unlike the house I grew up in.

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That's affirmative. Believe it or not though we do now have to deliver housing with minimum spatial design standards these days (HQI's etc for affordable housing at least) and there are calls for the same with private spec housing but the problems are twofold. Central government relaxing the rules to encourage developers to build out and not sit on their land banks (to solve the lack of homes etc) and also the cost of land itself. Many don't realise but the cost of land in this country is on the whole eye-wateringly high, and a significant majority of the price you pay for a new home is for the land it sits on not the building itself. There's an old saying in property development, 'they don't make land anymore'! That said we have the lowest floor area / smallest new homes in Europe at the moment and until that legislation comes in we're stuck with it.

Not wanting to sound like i'm sticking up for greedy developers (even though they indirectly pay my wages!) but margins are actually quite tight these days believe it or not, and it's technically really complicated with tons of pitfalls, many more than many may realise.

Anyway back to Dimplex heaters which is the main thing :)

Spend money on the heat loss through the floor, before throwing more heat into the room.

See what insulation you can install in the garage ceiling, and if you have an in-insulated steel garage door - insulate that as well.

I’m sure there will be some sort of cork/laminate insulation you can lay in the room, before re-carpeting.

Not just insulation but air tightness, ask Can air get in there what can i do?

Carpet up seal round the gap between skirting and floor with clear silicon as minimal as to be effective
Go into garage seal ceiling to wall interface with fire mastic, any lager holes with fire foam before you add any insulation
Same for any door windows or openings, seal on insde.
Is there a gap under garage door, a couple of solutions here. Stop influx of air at any juncture.

If this room alone is cool try a rad upgrade, is it a single ? then P+ or double of same size be an easy start

I do suspect poorly located stat

Its not beyond the realms that the insulation was ommitted during construction, lads on price, pressure to make money, slack management.

Before doing anything, I’d rent thermo visor and check where the cold comes in.

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Originally Posted by Normunds

Before doing anything, I’d rent thermo visor and check where the cold comes in.

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Heat transfer is hot to cold

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Originally Posted by blackal

Spend money on the heat loss through the floor, before throwing more heat into the room.

See what insulation you can install in the garage ceiling, and if you have an in-insulated steel garage door - insulate that as well.

I’m sure there will be some sort of cork/laminate insulation you can lay in the room, before re-carpeting.

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Garage ceiling should be double plasterboard to conform to building regs?.

A layer of Kingspan would do wonders - the thicker the better.

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Originally Posted by cman

Following with interest.

Would be good to know the pros/cons for gel based vs oil base vs electric panel.

Coincidentally, an advert for this just came on TV: https://www.fischerfutureheat.com/el...store-heaters/ - first time I've heard of them...

Better looking ones here - but interested to know how effective they really are:

https://www.amazon.co.uk/s/ref=lp_31...2&rnid=3147661

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My Mother’s only heating is with those Fischer heaters. My Father was taken in by the sales patter and I think they were very expensive and of course cost a fortune to run. They would have been better off with traditional night storage heaters (don’t have gas).

For the OP’s needs any electric heater will cost pretty much the same to run and for one room the added cost of the electricity won’t be that prohibitive. Don’t know if wireless thermostats are widely available with electric heaters but good to have it separate from heater itself if possible.

For fire yes. 30 mins on standard two storey residential.

I reckon there should be some mention of risk assessments at this point :)

Sent from my Pixel 2 using TZ-UK mobile app

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Originally Posted by Chris_in_the_UK

Garage ceiling should be double plasterboard to conform to building regs?.

A layer of Kingspan would do wonders - the thicker the better.

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Sorry forgot the quote!


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I’m guessing the room that’s cold won’t have thermostatic valves on radiator as there’ll be a wall mounted control of some description.

In which case close the door of that room to allow the heat to build.

Jim

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Originally Posted by Kingstepper

My Mother’s only heating is with those Fischer heaters. My Father was taken in by the sales patter and I think they were very expensive and of course cost a fortune to run. They would have been better off with traditional night storage heaters (don’t have gas).

For the OP’s needs any electric heater will cost pretty much the same to run and for one room the added cost of the electricity won’t be that prohibitive. Don’t know if wireless thermostats are widely available with electric heaters but good to have it separate from heater itself if possible.

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Have to disagree on the Fischer heaters, my other half switched from Econ 7 to a Fischer heater and loves it. The cost to run isn't hugely different because now she's not forced to run oil filled radiator or the fan in the bathroom. Yeah it was pricey but her flat is warm now for the first time.

I'd have them.

Those two external walls won't be helping. Is the room big enough to bear some retrofit internal insulation?

You'll get an IR thermometer from amazon for fifteen quid, might be a useful thing to identify where the cold is coming from*.

*Strictly speaking cold doesn't come, heat goes.

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Originally Posted by gilford

I do have zones, all of the downstairs underfloor is zoned for each room and all work independently, upstairs is its own zone and each rad has a TRV.

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I have this setup, but as a two stories throughout.
I've never turned the upstairs heating on in 3 years because the downstairs bleeds enough to upstairs.

- - - Updated - - -

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Originally Posted by paulpsz008

I have this setup, but as a two stories throughout.
I've never turned the upstairs heating on in 3 years because the downstairs bleeds enough to upstairs.

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Could you turn off the rest of upstairs at the TRVs?

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Originally Posted by gilford

Thanks for the replies this far gents.

The floor is timber with plenty of insulation (I’ve checked)

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Do the joists create a thermal bridge or is there a continuous layer of insulation cross the floor or ceiling? I think for best performance you would want a floating floor over a layer of load bearing insulation.

As others have said I would consider further insulating the ceiling of the garage and or below the floor with a continuous layer of insulation.

Can’t you just turn the room stat in the upstairs hall up and turn all the trv’s in the individual rooms to the required temp and have the daughters up full, heating keeps running, individual rooms turn off and daughters room keeps heating as stat keeps calling for heat